1. Field of the invention
The present invention relates to electromechanical timers used in controlling appliance functions in which the level of a function is selectable, such as the high, medium and low heat levels in an automatic dryer, and more particularly to such a timer in which the resistor or capacitor that provides differentiation between level settings forms an integral part of the switch circuit structure.
2. Description of the Prior Art
Electromechanical timers are widely used to control functions in automatic appliances. Such timers utilize a cam driven by a motor to activate switches which control appliance functions. Generally the cam and at least the switch blade portion of the switch structure are enclosed in a housing. The motor is generally mounted in a sub-housing and drives the cam through a gear train. The switch structure generally comprises one or more switch blades that are movable by the cam, one or more contacts mounted on the blade, one or more contact supports and contacts mounted on the supports, switch terminals mounted exteriorly of the housing, feed-throughs which connect the contact supports and blades inside the housing to the terminals outside the housing, and terminal straps which may connect terminals or terminals and feed-throughs.
Often a timer is required to control not only the timing of appliance function, but also the level of the function. For example, the high, medium, and low heat levels of conventional automatic clothes dryers are selected by setting the dryer timer to either a high, medium or low drying "cycle". In prior art timers, such different function levels are implemented by providing a plurality of electrical circuit paths, one or more of which is selected by setting the timer "cycle" which activates a switch to connect one or more of the circuits. The circuits differ in resistance and/or capacitance to provide the different function levels. In the prior art timers, the particular function levels are determined by the appliance manufacturer by soldering or otherwise connecting the leads of a conventional axially leaded capacitor or resistor to female terminals which terminals are connected to male timer terminals exterior of the timer housing. Often it is found to be necessary to place insulation over the resistor and/or capacitor leads to prevent shorting.